CoMP Movie

Brightness of an erupt­ing solar prom­inence taken with COMP on March 9, 2004.
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COSMO dome

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The NCAR High Altitude Observatory, The University of Hawaii, and the University of Michigan, propose to build a COronal Solar Magnetism Observatory (COSMO) facility for use by the solar physics research community. The facility will take continuous daytime synoptic measurements of magnetic fields in the solar corona and chromosphere, in order to understand solar eruptive events that drive space weather, and to investigate long-term phenomena. The primary instrument is a 1.5-meter coronagraph with two detector systems, a narrow-band filter polarimeter and a spectropolarimeter. Supporting instruments are a white-light K-coronagraph, and a chromosphere and prominence magnetometer. NCAR is funding the COSMO K-coronagraph which will be deployed to the Mauna Loa Solar Observatory in early 2013 to replace the aging Mauna Loa Mk4 K-coronameter. Please see the K-coronagraph page for more information.

New prototype instrumentation developed at the University of Hawaii and at HAO/NCAR have demonstrated that measurements of coronal magnetic fields are now possible. New scientific discoveries have already resulted from these breakthroughs, and a facility that includes a large-aperture solar telescope is a compelling next step to advance research into the solar corona. The observational program emphasizes scientific community involvement, including an open data policy, student participation, and public access to scientific results.


The CoMP instrument can observe the coronal magnetic field with a full FOV in the low corona (~1.03 to 1.5 Rsun), as well as obtain information about the plasma density and motion. Like Solar-C, CoMP records the intensity and the linear and circular polarization (Stokes I,Q,U,V) of the forbidden lines of Fe XIII at 1074.7 nm and also at 1079.8 nm. In addition to detecting the POS field direction and the LOS field strength, CoMP also measures the LOS plasma velocity from Doppler observations in the wings of the line intensity (Stokes I), and the POS density from the ratio of the lines at 1074.7 and 1079.8 nm. The CoMP instrument was deployed to the Mauna Loa Solar Observatory in 2010 and has begun acquiring routine scientific quality images as of October 1, 2010. Data will soon be available via the Mauna Loa Solar Observatory web site. Read more about CoMP >>

Solar C

The Solar C instrument is a 0.5m off-axis coronagraphic reflecting telescope which is located on Haleakala adjacent to the Mees Solar Observatory. The coronagraph records the intensity, and the linear and circular polarization (Stokes I,Q,U,V) of the forbidden lines of Fe XIII at 1074.7 nm. Read more about this instrument at the Solar-C web site.